1. Technical Field
The present invention relates generally to an interference cancellation repeater and repeating method and, more particularly, to an interference cancellation repeater and repeating method that are capable of more precisely cancelling a feedback signal without distorting a signal.
2. Description of the Related Art
In a mobile communication system, repeaters are installed in order to cover radio wave shadow areas. In the case of a repeater having no interference cancellation function among such repeaters, if signals of input and output antennas are not isolated from each other, the signal output from the output antenna of the repeater is input to the input antenna of the repeater again, thus resulting in an oscillation phenomenon attributable to the feedback signal. As a result, signals cannot be smoothly served, which may have an adverse effect on products. For this reason, in the case of a repeater installed in an environment in which an oscillation phenomenon is generated, the repeater outputs signals of reduced output intensity, which generates another shadow area.
In order to overcome such a problem, an Interference Cancellation System (ICS) repeater was proposed. The ICS repeater cancels a feedback signal through digital signal processing. However, a conventional ICS repeater is problematic in that the time it takes for a repeater system to process a signal is increased by the performance of an unnecessary processing task for cancelling a signal determined to be an interference signal from an input signal even when there is no interference signal and in that a repeated signal is influenced by a noise signal because noise is generated in an empty frequency domain.
In relation to the ICS repeater, Korean Patent No. 0879334 discloses “Micro Integrated Wireless Interference Cancellation Repeater and Method thereof.”